A reef aquarium is a wonderful picture for the aquarist or anyone else to watch. Once the reef is complete often the aquarist will wonder if there is any way it can be ‘improved’. Sometimes the diversity of life can be widened thus adding to interest.

A creature that is definitely different is the banded brittle star, properly called Ophiolepis superba. It is a creature of the coral reefs and has no difficulty in moving among the rocks and over sand. It is a scavenger and should not harm corals, small mobile invertebrates or fish. It is reasonably easy to keep, in other words reasonably hardy. On purchase the brittle star could be say 4″ (circa 10cm) and could grow to say 10″ (circa 25cm) arm tip to arm tip, though likely to be smaller in an aquarium. The suggested minimum size for the aquarium is 30 gallons.

When a brittle star is introduced to the aquarium the aquarium must not be newly set up. This is because stability is required – the biological system (ammonia/nitrite/nitrate) should be completely stable. Once this is proven by testing over time the next requirement is stability of the seawater specific gravity (SG), there should not be any variation, except very small because of say evaporation before a top-up. This is also proved by regular testing. The brittle star is sensitive to sudden salinity variations. So the aquarist should be certain that the SG parameters are acceptable.

The banded brittle star will live happily in a mixed reef system and as it is a mixed reef it is unlikely there will be certain fish present, for example angels (excluding the dwarf types), larger wrasses, triggerfish etc. A larger crab or harlequin shrimps will also bring problems. Though unlikely to be present, a predatory starfish will cause trouble. If any of the aforementioned types are present then do not introduce a banded brittle star as it is likely to be generally investigated, nibbled or worse.

Once the decision has been made to have a brittle star then certain procedures should be followed. The dealer should bag the star underwater being very gentle. When travelling, unless the journey time is very short, provide some insulation around the bag to conserve heat. Once home the bag should be floated in the aquarium and the acclimatisation procedure patiently followed. Using a teaspoon remove the first teaspoon of seawater from the bag and discard it. Place a teaspoon of aquarium seawater in the bag, leave for a few minutes then repeat. Keep doing this for an hour or more, whatever is needed, depending on the size of the bag and the amount of seawater to be changed. After the appropriate time the star will be ready to go into the aquarium. Gently and very slowly allow the free space in the bag to fill with aquarium seawater. Lower the bag into the aquarium as close to the bottom as possible and gently turn so the star can escape, it is likely to hide fairly quickly. The star will find a refuge among the rocks but, for luxury accommodation, a large clam shell or two is ideal.

Brittle stars are efficient nocturnal scavengers but should be fed. Feeding should start as soon as possible after introduction to the aquarium, say after the first night and towards the end of the first aquarium lights on period. The food should be fresh or defrozen fish etc, cut to about the size of a pea. Place the morsel as close as possible to the star, hopefully any seawater current will not move the food. Once the star has settled it is likely to be seen when the lights are on, and could respond to food availability in the same period. If this occurs, feed the fish then the star if the fish steal the star’s dinner. One feed a day should be enough, reduce the feeds if obviously required.

So why is the word ‘brittle’ used in the name? This is because the star can shed an arm or more as a defensive mechanism (they grow back), this can also occur if the conditions are too extreme. Fortunately, the banded brittle star is reasonably hardy and doesn’t shed an arm for little reason.

The banded brittle star can be obtained fairly easily but there is a warning (well, there has to be at least one!). The colours can vary quite a lot though not extremely so. If the dealer is selling some called ‘green brittle stars’ don’t buy one as these are predatory unlike the banded brittle star.

The reef aquarium can be so interesting and, once settled and even coming out in broad daylight, the banded brittle star certainly adds to it.

There are many beautiful fish available to the marine aquarist and one of these is the Emperor Angelfish, properly called Pomacanthus imperator. Purchasing this fish when young gives the aquarist in effect two fish over time.

Some fish can be recommended without qualification as they are not problematic. This is not so with the emperor unfortunately. There are clear constraints and also the fish could find the surroundings too much to its liking!

First it is always assumed that seawater quality is excellent, as it should be of course – this is a requirement for all marine inmates. The next problem is size, or eventual size anyway. Many emperors are sold as juveniles at say 3″ (circa 8cm) or so. They are so beautiful that the aquarist could be tempted and lose that oh so important discipline. The fish is transported home and settles well. Unfortunately, this little fish can grow to around 1ft (circa 30cm). This is clearly going to be a problem for many aquarists as their aquarium just isn’t big enough. The minimum sized aquarium should be 100 gallons, better around 150 gallons or more, the amounts exclusive of any sump. If the aquarist has an aquarium of sufficient size, fine.

The fish is not for a reef aquarium. That short statement knocks the suitability of the emperor on the head for many aquarists even if their aquarium is large enough. Again, large aquarium or not, resist the temptation because the emperor could find your reef very likeable, including the corals, tube worms, shrimps when moulting etc. They are likely to be nibbled at or eaten, not something that is going to endear the fish to the aquarist. So there’s the next constraint, the emperor needs a fish only system. It should also be remembered that the emperor will not be happy with another emperor, or any fish with colouration similar to its own. So the large aquarium could have an emperor plus a few others, remembering that fish size reduces the number of fish the aquarium can house.

If the emperor is still considered a potential addition to the aquarium, then feeding is the next consideration. Emperors are not particularly picky but do require a suitable diet to maintain colour and health. There isn’t any reason why decorative ‘live’ or ordinary marine suitable rock should not be in the aquarium, remembering that swimming space for the fish is required. If this rock has algae growing on it then the emperor will graze it regularly. It’s unlikely that the algae will survive and reproduce quickly enough, so various chunks of rock can be selected and, one by one or more as necessary, taken to another tank or lit sump and left to allow algae to develop. This way there will nearly always be a rock for the emperor to graze on. This green diet can be supplemented by the use of blanched lettuce leaves and algae that can be purchased from a shop. ‘Vegetarian’ flakes could also be of some use. The green content of the diet should amount to at least one third, the rest can be made up of frozen food such as shellfish, krill etc. Marine flake food can also be fed. Failure to feed a suitable diet could well result in a ‘sad’ fish – malnourished, poorly coloured and ill. Juvenile fish are likely to begin to fade more quickly.

Juvenile Emperor Angelfish

Ok, so the aquarium is large enough, the aquarist is happy with the restrictions of size and potential tankmates, and diet will be properly followed. The beautiful emperor will be a wonderful addition, it shouts of the colour and vibrancy of the reef.

The extra that the aquarist achieves is, as mentioned in the first paragraph, the equivalent of two fish. When obtained as a juvenile the colours and patterns are completely different to the adult and the gradual change can be observed. Both versions of the same fish are beautiful, though the adult emperor is more imperial. I don’t know if the correct reason for the two different fish patterns is known, but it has been thought that the juvenile is protected from any unwanted attention from adults.

It must be remembered that the emperor is not suitable for every aquarium, space is needed and if a coral reef is desired the fish is not suitable. There are other fish of this family that are similar in this respect. Discipline, patience and research are the watchwords – there are other fish that can enhance and not damage a reef and plenty suitable for those with a smaller aquarium. But if everything is suitable for the emperor – including the aquarist! – then wow, all acknowledge the emperor of the reef.

It’s exciting, setting up a new marine aquarium and at the same time it can be frustrating as there is a fair amount to sort out. Initially it can be confusing obtaining the information on this and that and what is actually needed followed by the actual size required. We get there in the end though and it’s certainly worth it.

One of the reasons why the aquarist is so careful when purchasing equipment is to make sure the eventual livestock will be adequately supported. It’s also to make sure the amount of money spent is necessary and not wasteful – nothing wrong there.

The aquarist eventually gets to that very essential support for the aquarium, the biological filtration. This is provided by bacteria and deals with the deadly ammonia and nitrite, also nitrate. These are generated within the aquarium by the livestock and the first two are killers. The only acceptable reading for these is zero. Nitrate is not deadly but can cause real problems if not controlled, such as excessive nuisance algae. The guideline maximum reading for nitrate for a reef tank is 10ppm (parts per million) and for a fish only 30ppm. Both should be as low as possible.

The aquarist’s discovery of the biological cycle (ammonia to nitrite to nitrate) and the recommended way of dealing with it gives rise to the ‘cruelty’ question. The modern recommendation is to use live rock. Why is it called ‘live’? The rock is loaded with the bacteria that deal with the above-mentioned ammonia, nitrite and nitrate. The aquarist knows that in the wild the fish live among rocks and this seems the best way of providing a top line environment. It is. Another advantage is that live rock can deal with, within reason, the full biological cycle (also known as the nitrogen cycle).

Live rock is expensive. Putting a couple of rocks in is not sufficient, there must be enough to support the livestock. Sufficient rock as quoted by the dealer could be just too much money. Should the aquarist give up and not proceed further because ‘the best’ will not be available? There’s a simple answer and it is ‘No’!

The requirement is to give the livestock a fully supportive environment. So there is a need for rocks so the fish etc can find security (and make the view for the aquarist more natural of course). They don’t need to be live. Wait though, don’t buy any rocks yet.

The biological cycle can be achieved by using a powered cylinder filter. This is a unit that has an integral pump sitting on or in a cylinder that is filled with biological filtration material. Well, that’s not completely correct, there is filtration material to remove debris first to protect the biological material. It is necessary and really important to make sure that the lift rate of the power filter is sufficient to take the seawater to the highest point required, often the top rim of the aquarium. This distance can be quite large as most power filters sit below the aquarium in a cupboard. Manufacturers often give this information.

The power filter price is acceptable so all is sorted then. Yes it is but there has to be a downside of course. Live rock will deal with the complete biological cycle. The power filter will not, nitrate will be produced in the aquarium but not removed by the filter. Why? The bacteria that deal with nitrate require an oxygen poor environment, this is achieved deep in the live rock but the seawater flow through the power filter is oxygen laden. The nitrate has to be controlled by not overstocking, not overfeeding and completing regular partial seawater changes. These are required anyway so it isn’t a big deal, though the partial seawater changes could need to be a little larger. The guideline for these is 10% weekly of the total aquarium gallonage including a sump if present. The amount can be adjusted as the aquarist’s experience grows.

Ok, the power filter it is then. What of the rocks? Natural cycles occur within the aquarium and bacteria that are required for the biological cycle are present within the aquarium up to a point not just in the power filter. So when the rocks are bought don’t buy solid dense lumps, get craggy porous ones of various shapes ensuring they are marine aquarium suitable. They shouldn’t be powdery or flaky. Once the reef is made, leave them alone apart from any initial necessary adjustments. These rocks will become home to bacteria and will also be able to house those that deal with nitrate as they are deeply porous. This takes time and requires patience, it will not happen overnight or over a few weeks. I did this and it took 10 months before I could safely turn off the power filter (well, remove the biological material anyway, the power filter is still in use).

To check for rock becoming live is easy but great care is required. Once the rocks are aged for many months or even up to a year the power filter can be turned off and a very regular check for ammonia, nitrite and nitrate done. Any sign of the former two and the power filter is back on. WARNING – There is a danger and it is real and needs attention. If the power filter is turned off and the rocks are not sufficiently ‘live’, the power filter needs to be turned on again. If the power filter has been turned off for a good while the biological capabilities of the filter could be seriously damaged and the livestock could be in danger.

To mainly avoid the above described danger the aquarist could have initially obtained two smaller power filters (remembering to check for the lift capability). They are both loaded with biological filtration material. When the time comes to try turning them off turn one off. Leave the other running for a month or more. Test for ammonia and nitrite. When all is found clear for a month or more turn the other off. Continue testing. The bacteria on and within the rock should increase as the impact of the power filters is removed. Don’t take chances, patient testing and time is required.

The aquarist could be quite happy to leave the power filter running, nothing wrong with that. The livestock will be quite happy and healthy, fish and/or corals. It just means a little more maintenance, including cleaning the filtration material in the power filter on a regular basis (only the initial filter material to remove debris, not the biological material! The debris material can be cleaned under a tap. If absolutely necessary, the biological material can be very gently washed in aquarium seawater). Also perhaps there could be a need for larger partial seawater changes to reduce nitrate.

Some requirements for the marine aquarium are essential, such as heater(s), circulation pumps, protein skimmer etc. Rocks make the scene look natural and also provide hiding places for the livestock which reduces stress. If ‘live’ rock can be used, great. If not then ‘dead’ porous rocks could be obtained and when they have coloured up they’ll look lovely. If power filters are in use for biological filtration and the aquarist has doubts or worries about turning them off, don’t.

It has been said many times that the successful marine aquarium is a spectacular sight: beautiful fish and corals with matured reefwork making it all look very natural despite the glass box.

There are many fish that could be chosen to help produce the scene as described above and it can be confusing. As usual the aquarist needs to show patience and do research so that the fish (or coral) chosen is compatible and will not cause disruption or grow too big. The angelfish are a clear choice as they display lovely colours and certainly enhance any display.

Hang on though, what about size and hardiness? Size is the first problem as many angels, such as the Emperor and Koran can grow to 12″ (30.5cm) or so, much too big for many home aquariums. There is a group of angels that only grow to between 2″ to 5″ (circa 5 to 12.5cm) and these are the main interest to the home aquarist with a smaller aquarium. Understandably they have been called ‘God’s gift to aquarists’.

When considering purchasing the fish at the shop the usual rules apply – does the fish swim and breath properly, are the fins solid and not ragged, is the body clear of marks and well shaped and does the fish feed. A dealer will usually offer a little food to the fish to demonstrate the last point. Take time there isn’t any hurry.

So then, the really beautiful – it could be called spectacular – flame angel. The proper name is Centropyge loriculus. It is one of the larger dwarf angels and is capable of growing to about 5″ (circa 12.5cm). It is not the hardiest of the dwarf angels but is reasonably so in a high quality environment. The home aquarium should be fully matured, not newly so, as the flame angel likes to graze over rockwork looking for small surface algae and other morsels to eat. To maintain health and colour it needs green food, one reason for the requirement for a mature environment – if green food in a small quantity is not available then small supplements are required from time to time. Overall the fish has an omnivorous tendency going for most things available including flake. It is generally safe with corals though it will often nibble at green looking specimens but usually doesn’t do any damage. To avoid stress there needs to be rock work so that the fish can choose a place to hide in the dark. It seems clear that the best environment for the flame angel is a reef system, or less so a low stocked mature ‘fish only’ containing rock work.

So no problem then if the fish goes into a reasonably aged environment with rocks? There is usually something and so there is with this fish. Despite the ‘angel’ tag it isn’t completely sweet as it is quite bad tempered and is likely to chase off other fish that come too close, unless they are clearly bigger. Also, there is a risk of trouble if other fish have any colour that is close to that of the angel. So that’s a further consideration to bear in mind. Like damsel fish, it could be better to make the flame angel the last introduction to the community.

I have had a flame angel for 11 years in my soft coral reef system. It has demonstrated the bad temper mentioned earlier but has not caused damage to the other fish, a blue damsel and a royal gramma. The flame angel has chased the damsel but the damsel is much too quick, disappearing into rockwork, and the royal gramma hangs about its favourite hidey hole a lot though it does go further afield regularly. The royal gramma is ignored now for most of the time as it has grown, at least I assume that’s the reason why. As far as corals are concerned (all soft corals) the flame hasn’t damaged any at all ever. The fish does gently ‘mouth’ the green star polyps (Pachyclavularia) when passing but as said never causes any damage.

There is another safeguard against innapropriate purchase of a flame angel and this is price. The fish is usually quite expensive and this alone will make the aquarist pause for thought. However, if the price is right, if the intended high quality environment is mature and if the tankmates are appropriate the flame angel will make a superb addition.

The two just don’t go together, or rather they shouldn’t. The marine aquarium is a peaceful and relaxing world that the aquarist can view with pleasure. The pressures of day to day living can be reduced by just sitting and gazing. Well, usually anyway.

With the marine aquarium there are two kinds of stress, the first hits the livestock and the second the aquarist. The aquarist normally isn’t stressed at all without the first type and it’s the aquarist who for the most part causes the personal stress. All a bit crazy really.

It has been said that environment is everything. This applies to all species of life no matter where or what. Make the environment poor and there will be repercussions: moderate, severe or deadly.

So the fish and , if a reef system, the corals are heavily dependant for health on their environment. Now it’s clear where this is going! The aquarist has to ensure that the environment for the livestock is correct and continues to be so. When the system is constructed there must be adequate means of maintaining, say, salt water quality, for example a properly sized protein skimmer. The temperature of the seawater needs to be correct, so there needs to be adequately sized heaters. All equipment needs to be adequate and the essential items present. The seawater needs to be of high quality without excessive nitrates (leading to yukky algae) or the deadly ammonia and nitrite. Those are the obvious things but it goes on from there.

Whether the system is a reef or fish only there has to be adequate places for the fish and any other lifeforms to hide, so rocks need to be used to create caves and crevices. Providing rocks in a fish only system reduces the seawater gallonage and reduces the fish carrying capacity but at the same time reduces or removes stress. The fish don’t know they are in an aquarium, as far as they’re concerned the need to hide from predators at certain times such as at night is essential. Hide or die. Even if there are rocks present there shouldn’t be too many fish or some are going to be stressed as they fail to find shelter. Fish overstocking based on gallonage is bad and also based on security.

Even if security is adequate there will be stress if timid fish are in the presence of aggressive ones or even a predator. That fish that attracts the eye of the aquarist, is it compatible? ‘Compatible’ is a very important word in the confines of an aquarium.

Fish stress can lead to severe problems in the aquarium, some fish could be so nervous that they don’t take food because of the presence of other more aggressive ones and could even starve to death. Or fish could have torn fins or develop disease.

So the aquarist is clearly doing no favours to him/herself by not providing a high quality environment. When keeping a marine aquarium was being considered sick fish and green yukky (technical word that!) algae were not included. The marine aquarium is supposed to calm and give enjoyment, hence the presence of an aquarium in some dentists’ waiting rooms. The aquarist in some cases is his own worst enemy, buying on sight and/or on impulse. There isn’t any need for it, none at all. There is a huge amount of information available on the internet and in books and none of it is difficult, a scientist’s white coat isn’t required.

So sit and watch the aquarium in fascination, the colour and movement of one of Mother Nature’s great achievements. Feel any stress drain away. Or note the unwanted algae, the sad looking colour faded fish, the closed up corals and the scummy seawater. The stress generated in the struggle to recover the aquarium investment is definitely not pleasant.

Maybe that’s it. Maybe that’s the difference between success and failure. Maybe the desire to recreate a marine scene and protect the life in it, rather than spend money on a glass box and put fish in is the difference. The first shows genuine respect and, though Mother Nature doesn’t give a cast iron guarantee, pleasure and a stress free hobby should be on the way.

Oh no, this sounds really serious! Sounds like everything has failed, all pumps refusing to pump and the like. What a nightmare that would be. But no, the nearest thing to that would be a power failure as equipment nowadays is generally reliable.

What this is all about is the passage of time and the effects. Year in, year out all is well and the aquarist watches his/her beautiful aquarium and the changes occuring – fish grow, sadly perhaps one dies, corals change shape and even move by re-attachment. The reef becomes more like a miniature wild reef, tiny creatures scurrying about in the dark avoiding the dangers of predation. A fish only system also changes and matures, many of these systems use rocks as decor and these change colour and develop different coloured algae as the fish grow. The aquarist assists in this by maintaining the system – cleaning the viewing glasses, completing partial seawater changes, at the same time siphoning rubbish out as far as possible.

Now we get to it, it’s this rubbish that’s the problem after many years. We aquarists vary in how keen we are, some are enthusiastic and some carry out maintenance because ‘I have to’. I like the first version the most but it doesn’t really matter as long as the maintenance is properly completed. No matter how well the maintenance is done eventually a problem can arise. When the aquarist completes a partial seawater change usually the old seawater is siphoned out of the aquarium, this siphoning also removing debris which can then be discarded. Unfortunately, debris has an unhelpful tendency to gather in inaccessible places such as under and behind rocks and corners. Helpful though the siphon is there isn’t a way of reaching these hidden accumulations.

Well, that’s not true, there is. Eventually the debris has to be removed by dismantling the aquarium. Just thinking about that could cause an aquarist with a beautiful aquarium to tear his hair out! Remove all those rocks, sand, corals, fish and anything else kept. The stress on the aquarist and the livestock is high. But if the dirt is clearly excessive, and it is easy to know when it is, a clean up must be done. First, discipline – do it. Pick a time and day to do it when there isn’t going to be interruptions. Ensure there are enough containers in which to place rocks, sand, seawater and creatures. Mix plenty of new seawater to act as a top-up supply, none will be wasted as any excess can be used towards a later partial seawater change . Cloths need to be available to cover the floor area. A couple of beers could be standing by too! Take a photograph of the aquarium through the viewing glasses, if possible from both sides and the front, this should assist in re-construction.

There will be some damage to the view but it should be minimal. Grit those teeth! Ensure hot heaters are not exposed to air. Siphon some seawater into the container that is to hold rocks. Now take the top visible rocks out and place them carefully in the container. If it’s a reef aquarium there will be corals so these must be carefully placed to keep the corals on top. Now take the lower rocks out and place them on the rocks already there avoiding any corals – use a separate container if necessary. This puts them in the correct order – bottom and top – for putting them back.

Siphon out as much of the remaining seawater as possible, avoiding dirt. Running the seawater through a filter cloth could help. Ensure seawater goes into the container that will hold livestock. The seawater being saved will be going back into the aquarium. Leave a few inches of seawater in the aquarium for the fish and any other livestock.

It is a good idea to use two nets to minimise the time spent chasing fish around which causes more stress to the fish never mind the aquarist. When they are caught gently put them in a container. Siphon out all remaining seawater as far as possible avoiding dirt. Ensure the seawater in the livestock container does not cool excessively – use a heater if necessary.

Now the clean-up can commence. Remove the accumulated dirt completely and dispose of it. Work quickly but ensure that dirt, including that on the glasses not normally seen, is removed. Now things are progressing. No beer yet though. Thoroughly clean any sand that is in use. This can take some time. The use of tap water for this is acceptable, the sand can be flushed in a bucket until it is clean, just keep tipping out the tap water after each stir with the sand still in the bucket. Note: cleaning sand does not include any DSB (deep sand bed). Let the sand drain so that as much tap water is removed as possible.

Everything clean? Right, into reverse then. Return the lower rocks first trying to place them where they came from. This will not be completely accurate of course. When the lower rocks are in and stable, the upper rocks can go in. The tops of the upper rocks are evident by the different colour as they are exposed to the light and of course they could have a coral attached. To assist use the photographs if they were taken. Ensure the rocks are stable. Now place any sand required into the aquarium.

Return the seawater from the rock container to the aquarium, ensuring that any dirt is not returned. Return the seawater from any additional container that was used. Check the level and top-up from the new mix as necessary. Turn on the aquarium heaters and other equipment once the seawater is at the required level, but leave the lights off. Again using two nets if needed, catch the fish plus any other livestock and gently return them to the aquarium. Do not expose shrimps and similar to the air. There isn’t a requirement for the livestock to be acclimatised as they are essentially in the same seawater. Take this opportunity to check the rock structure once more, ensure it is stable. Leave the lights off until the following day, this will help the livestock to de-stress. In the same way, do not attempt to feed them. Let them have some quiet.

Put away all the bits and pieces and clean-up the area if needed. Now the aquarist can de-stress. Have a beer, you’ve done well! The aquarium scene will repair quite quickly as damage to the rocks and that on them should be minimal. Mother Nature will re-assert herself.

There is one advance on the system that can be made at a major clean-up time as described above. It’s also achievable when a new aquarium is being set up. This advance will delay the ‘total breakdown’ requirement considerably and is recommended. For more information go to the March 2011 Archives from the Home Page and click on the title ‘Keep It Clean’. I have this in my reef aquarium which has been running for 13 years, there is about 2 inches width of sloping debris at each end of the aquarium under the rocks and the rest is clean. No need for a breakdown, at least not for a considerable while.

The marine aquarium, be it fish only or reef, can be fascinating and beautiful. The reef aquarium is the one that attracts most aquarists and understandably so. Colourful corals sitting on rocks with various fish swimming about and maybe other lifeforms. Why not a hermit crab? They are different and interesting, sometimes amusing with their antics.

The aquarist needs to have some experience before considering a hermit crab. There’s a problem – how is ‘experience’ measured? Generally the aquarium must be fully matured not new and ready for stocking or not long after stocking, in other words reasonably ‘aged’, preferably six months at least. Seawater parameters, meaning temperature, pH, SG, ammonia and nitrite (the last two should never appear) need to be totally acceptable without high nitrates, the last indicates that overfeeding doesn’t take place. As an unscientific comment, the seawater needs to be very clean.

If the hermit crab develops a sickness it cannot be treated with copper. This is not a problem as they are already in a reef environment with no copper corals in the same way fish are.

Hermit crabs like a rocky environment with crevices and caves so the reef system is ideal. The fish that are in the system should be peaceful and small, not unusual for a reef system.

Though hermit crabs are not usually difficult to keep, they are a little delicate. This does not mean that they are fussy eaters or likely to be easily damaged, but they do suffer from a less than ideal environment. Therefore after being taken from the sea and transported they can often be below par and need a good environment and feeding to strengthen again.

When the crab is obtained from the store it should be transported home without delay. The bag should be hung in the aquarium to allow the temperature to equalise and a small amount of seawater discarded from the bag say every 10 minutes and replaced by aquarium seawater. Once this procedure has gone on for about an hour it should be safe to release the crab into the aquarium. Keep the bag and crab underwater and gently tip the crab out into a quiet corner as far as possible. Leave it alone and after a while the legs will appear and it will go off and probably hide though not all do, some start exploring immediately.

Feed the fish as usual and don’t worry if the crab doesn’t get any, wait for it to settle down, usually this doesn’t take long.

Hermit crabs get larger and need to adopt a bigger shell from time to time, so it’s necessary to ensure there are one or two sensibly larger shells lying about. The crab will inspect them and if interested change. The shells should be natural and not man-made ie plastic. From time to time the crab will get rid of its exoskeleton and this should be left in the aquarium as the crab could well eat it.

Feeding a hermit crab is not difficult as they aren’t fussy. Usually they’ll happily eat any algae available and also small algae pellets, just the one or maybe two. Fish food will also be consumed if any escapes the fish. To ensure they have enough, place some food – a bit of fish or shrimp – near them and see if it is eaten. It will soon be known how much the crab will eat in the same way as it is with fish.

So a hermit crab like other inhabitants of a reef system demands a quality environment. It also need some spare shells in case it needs to move to a new one because of growth. Also adequate feeding without overfeeding which again is the same as fish.

So next time there’s a visit to the fish store look for a hermit crab just for interest. If a purchase is considered find out the size it will eventually grow to. Also get a couple of shells for it to move into should it wish.

“The fish are fine under standard non-aquarium lights, even if I buy just white lights they are still ok. Why not corals?”

This is an understandable question. Marine reef fish come from the same areas as the corals so why spend more? There is a good answer and no, it isn’t just a good way of making money!

First let’s make a comment about ‘just white lights’. This can mean any kind of bulb. Marine fish will live happily under ‘just white lights’ as they need to see and basically that’s it. However, lights designated for marine aquarium use (for fish only this is usually fluorescent) should not encourage unwanted algae. Lights that have an unwanted spectrum particularly in the red area can. So two tubes, one marine blue and one marine white will be better. Two tubes allow for a ‘dawn/dusk’ sequence (using two timers, see below) and with some fish the light output enhances the fish colours.

So what about corals? With fish it can be an advantage to use blue and white as above. With corals it is essential. Why? Within the flesh of light loving corals are small single celled algae called zooxanthellae. These cells are very tiny, a square millimetre could hold about 10,000! They live as tenants, the rent is nourishment for the corals. The zooxanthellae can supply between 60 and 150% of the coral’s energy requirement*.

How do the zooxanthellae obtain the nourishment for the corals? In the same way as living plants, including visible algae do – from the sun. This is known as photosynthesis. Corals having ‘tenants’ possibly started because tropical reef waters are nutrient poor.

Now we need to go a little further. We’ve mentioned marine white and blue as needed colours, this is because light is lost in seawater and different colours are lost at different depths. Some corals live near the surface, others live deeper down. High penetration of seawater is achieved by blue light and it is known that zooxanthellae are able to make good use of this light. The blue light gives a lovely colour to the aquarium picture on its own, but the light is balanced by the white light. Also, as with fish only, the aquarist can create a ‘dawn/dusk’ sequence. The sudden application or withdrawal of light isn’t good, so the blue lights can come on say 15 minutes before the white (dawn) and reverse at the end of the day (dusk). The overall message is, for success with corals the lighting should be correct.

There are choices as usual and technology advances all the time. However, in my view simplicity isn’t a bad thing and so ‘straightforward’ lighting is required.

First, there are fluorescents which are readily available and suitable. Ready made lighting canopies can be obtained containing more than one fluorescent but let’s keep costs down and buy single tubes. Check the length of the aquarium and make sure the ones we choose will fit. Consider reflectors for the tubes and obtain the maximum that, put in lengthwise, will fit across the aquarium. The number of reflectors dictates the number of tubes of course. Obtain marine blue and marine white tubes, if the reflector number is even make one half blue and one half white. If the number is odd make the extra one white. Now it is easy to get the correct power units – these can be obtained so that two tubes run off one so creating more simplicity. Two electric timers are needed for the ‘dawn/dusk’ sequence. The supplied power connectors for the end of the tubes are specially designed so are safe if the reflectors/tubes sit on the glass cross bars (but does not remove the need for caution when electricity is close to seawater!). The usual tubes used are called T5’s. Fluorescent lighting is reasonably cheap to run and does not emit excessive heat. The tubes need to be changed at the latest once a year, probably better at 6 to 9 months.

So that’s simple and not a tremendous expense. However (oh yes, here it comes!) tubes cannot be used on any reef – it depends on the depth. The light has to reach the corals with sufficient power so research and/or advice is needed. There’s plenty of information available, including on this site.

Another popular lighting system is called metal halide. These come in prepared packages though DIY is available. Dependant on the length of the aquarium, one or more light units are hung above, often one for every 3 feet, not too close to avoid them being splashed (this is because the bulbs become very hot). The light unit(s) are connected to controllers which could have timers. The bulbs available are designed for marine use and come in various light types some being more white and others more blueish in appearance. Some aquarists make use of one or two marine blue fluorescent tubes as well, so the zooxanthellae are happy and a ‘dawn/dusk’ sequence can be achieved. The metal halide system is a very good lighting system for deep reef aquariums as light penetration is very good. Different power level bulbs are available, two being 250W (watts) and 400W. Reading those wattages gives a clue to the downsides, the first being they are expensive to run, more so the more bulbs there are. The second downside is the heat the bulbs emit which can quite easily heat up the seawater. This additional heat could be a real problem in summer when natural heat is higher as the seawater temperature increases – the heater(s) fitted will of course switch off but the temperature could continue to increase, even to the point where aquarium life is stressed or threatened. To resolve this problem could mean the purchase of more equipment, a cooler. So again research and/or advice is required. With the lights on between 8 to 12 hours a day electricity costs are going to be very noticeable, plus the possibility of additional problems as mentioned. The bulbs too will need replacing at generally the same periods as fluorescent lights.

Finally, there is now what appears to be an excellent choice of lighting. This is the LED system. Basically blue and white LED bulbs are mixed to give good coverage of the aquarium. The lights can be a DIY project, or purchased as an array that covers a large area of the aquarium surface. Alternatively, LED strips can be obtained, these are similar to fluorescent tubes and reflectors in size and are fitted in the same way though the blue and white is present in each strip. Though things are improving all the time the disadvantage of these systems is the high cost, particularly the ready built full array. The strips are not as bad though several are required. There are some definite advantages though. The first is the very long expected life of the LED bulbs which could be up to 20 years! The second is the low running costs – obviously they still need electricity but nothing near the demands of a metal halide system. The third is the heat output, it isn’t going to be a problem and will not normally affect the seawater. In some systems there is an in-built fan unit that directs any heat generated away from the aquarium. Another ‘advantage’, and this depends on how the aquarist views it, is the ability for example to simulate clouds passing over the reef. Most aquarists would probably view this as a non-essential high level luxury and fair enough. It is available in or with some full canopy arrays and will add to the already high purchase cost.

So special lighting on a reef aquarium is essential. It is of course up to the aquarist to decide which type, the decision will effect the later costs of running the system and the cost of buying it in the first place.

One thing is for sure. If the reef system is to be a success, if the aquarium is going to be as beautiful and interesting as it has the potential to be whatever its size, and if the aquarist is to meet the ongoing cost of running the system, the correct choices have to be made. So research and advice, then consideration. It’s worth it!

We more experienced aquarists tend to go on a bit about starting a new marine aquarium. This isn’t because we’re showing off our knowledge though there’s no doubt a bit of that arises occasionally, it’s because we’ve done things in the past that new aquarists often do – that is we’ve done things wrongly when setting up the system.

Having seen a marine aquarium, often a reef system, at the local dealers or wherever many state how beautiful they are and move on. Others state how great it would be to have one meaning the first step has been taken. Following this could be a look on the internet or a visit to the local fish store.

The next move, having looked at the available space and obtained any partner’s agreement, is to go and have a look at marine aquariums more closely. More often than not this means a trip to the local dealers. No problem so far.

The first aquariums to be considered are often ready built systems and this often delivers the first surprise – the cost. Most likely the first ready built system looked at is a big one and well equipped. If it can’t be afforded then downsize or consider the ‘put it together yourself’ variety. If one big or smaller can be afforded then the potential aquarist should go home and make price comparisons using the internet. If the local price is not acceptable then talk to the dealer. There are reasons why buying from a local shop is good, but there is a need to ensure the price is reasonable. If all is acceptable then it is really a good idea to consider a self built system too. Ask the dealer to quote a price for this for a same size system. If the ready built system still appeals, no problem. But wait.

Why wait? Find out what demand the system will have for electricity, then a cost per day, week, month and year can be calculated. Also, how many gallons does the system hold? There will be a cost for sea salt for the initial fill (though not accurate take 10% off the gross gallonage, this is close enough for a very rough net gallonage estimate) and also an ongoing cost for weekly seawater changes, the amount of the new weekly seawater, initially anyway is 10% of the net gallonage.

If everything is still acceptable, then there is a requirement to consider the cost and type of stocking. Under no circumstances should a marine system be overstocked. A decision is required – is it to be a fish only or reef system. Fish only can contain more fish subject to size, a reef less fish to help ensure seawater quality remains high. Take advice, look on the internet, consider, don’t just go ahead. If a reef is chosen, ensure that the lighting supplied with the ready built system is suitable for corals.

At this point another decision is required and again advice and consideration is needed. Biological filtration is required, without it or if it is inadequate there will be disaster! ‘Living rock’ in sufficient quantity and quality is the modern best way of biological filtration and in addition is wonderful for creating a reef (or rock formations if fish only). Unfortunately the rock is expensive. Another method of biological filtration is a correctly sized canister filter containing suitable materials. The big downside of the canister filter is that they do not remove all the ‘baddies’, one is left which is not particularly dangerous in itself but can lead to severe problems if unchecked (nitrate). Overloading the filtration by for example introducing fish too quickly can produce disaster, poisons can accumulate which will kill the livestock (ammonia, nitrite).

What about setting up a system by purchasing seperate components? Nothing wrong with that and cost savings can be achieved. Needed is an aquarium (surprise!), a suitable support for it (an aquarium full of seawater and rocks is very heavy!), biological filtration as above, a heater (or better two at half the wattage each), a thermometer so that the seawater temperature is monitored, a protein skimmer of suitable size for the net gallonage and lights suitable for the type of system being constructed. Also a control device is required for the lights as they will not be on all the time. Powerheads (water pumps) will be required to move the seawater and create flow – usually at least two are needed, it depends on the size of the aquarium if more are required. When the price for all of these is obtained if it is acceptable then fine. If not, downsize the aquarium or don’t proceed at all.

Anyone considering constructing their own system from seperately purchased components, if the cost is acceptable, should proceed as with a ready constructed system above.

There are four other very important bits to obtain and must not be missing on a new system. These are test kits for ammonia, nitrite and nitrate and also an hydrometer (the latter is used to check the ‘saltiness’ of the seawater, called the specific gravity).

There is one piece of equipment that is not usually listed as definitely required. This is the reverse osmosis (RO) filter. This filters tap water very thoroughly removing toxics that are detrimental – a good one will produce 90/95% pure water which is used to mix with the sea salt. It is a worthwhile addition as unwanted substances are not required in a marine aquarium. These filters are not hugely expensive and are recommended particularly as much of tap water destined for safe human use has unwanted content.

If the cost is found to be a little excessive on any aquarium component don’t be tempted to reduce the size of anything which is deemed correctly sized! Wait until the correct equipment can be afforded. It’s worth waiting or the cost further down the line, sooner or later, could be high.

The procedures mentioned are not meant to be the ‘a to z’ of setting up a marine aquarium, far from it, but a path to initially follow during the usually confusing early period. In truth, keeping a marine aquarium is straight forward provided all is well in the first place.

There are three words that cover the requirement for success and these are research, discipline and patience. Success is in the hands of the new aquarist. If the system equipment that is being used is fully adequate, if the stocking has been carried out correctly and if ongoing maintenance is adequate all should be well. There isn’t a cast- iron guarantee of success where Mother Nature’s creatures are involved but the aquarist can move the indicator for success very high up the scale.

So, exercise discipline and patience, wait as long as necessary, use adequate equipment and stock very carefully. Lots of information is available in books and on the internet and a knowlegeable local dealer should also give good advice as it is in his interest to do so. That successful marine aquarium is waiting to come to life.

Any potential marine aquarist could easily consider that the best source for advice when a marine aquarium is being considered is the dealer. This is completely understandable – who do we ask when there’s a problem with the car or TV or we want advice on a new kitchen?

This young couple went into a pet store and saw some fish and thought ‘what beautiful creatures’. They approached the assistant who advised them the common names of the fish and the couple bought two and took them home looking very pleased with themselves. A couple of days later they were back at the store and advised that the two fish they had bought had died but the other fish in the aquarium were perfectly fine. When asked they advised that the dead fish hadn’t displayed any sign of disease.

The shop assistant was quite puzzled and asked what type the other fish the couple kept were. The couple advised they were goldfish. ‘But the fish you bought need warm salt water’ the couple were told. ‘Oh’!’ they said.

It cannot be verified but the above short tale is supposed to be true. Assuming it is who was at fault, was it the couple or the assistant? At the end of the day it was the couple, if they had asked to buy the fish the assistant could quite reasonably have assumed they knew what they were doing. The final responsibility is with the home aquarium owner.

Marine aquarium shops are generally reasonable (but not overall), with some considerably better then others. To give good advice they need good information. A good experienced dealer will ask questions and advise ‘when’, ‘what if’ etc.

I used to use a local very small shop (sadly marine aquariums are no longer dealt with). The dealer realised very quickly that I knew considerably more than he did. To his credit he used this to his advantage, asking questions when I went in for a coffee and even occasionally referring other customers to me if I happened to be in the store. This doesn’t indicate I’m anything special but shows that he was doing his best for customers.

From time to time I use a much bigger, though not huge store about 40 miles away. I travel this distance because it’s worth it.

Going in to the store is a bit off-putting, there’s a quite narrow drive down the side of a house and a very small car park at the back. The building housing the store looks quite scruffy. However, inside it is well-ordered, the aquariums are clean and reasonably laid out. There are no struggling or dead creatures. They actually sell to the trade but are happy to serve the public too (just have to avoid the despatch day for the trade!). I wander around at my leisure and when I’ve identified what I want the assistant comes over. The price is confirmed and, if the purchase is for fish, they are held individually and carefully by net at the front of the tank for inspection. If I’m satisfied they are quickly bagged. Technicalities could be discussed and it’s obvious that the assistants have experience and are reasonably bothered about the welfare of the livestock. The shop also quarantines the fish stock and do not keep the salt water in the for sale aquariums dosed with copper.

The above is the type of shop that is gold to a marine aquarist – helpful, knowledgeable and to be trusted. However, as mentioned they can advise only on the information they receive, if they receive poor information it’s the aquarist’s fault and the aquarium life could suffer for it.

No matter how good a marine aquarium shop is, at the end of the day they need to sell as selling means survival.

The new marine aquarist needs to know what type of aquarium is wanted, the space for it and the basic equipment required. Equipment prices can be checked on the internet for comparison purposes. The internet and/or books can supply lots of basic information. Once the information is held and covers the basics then try the local dealers and try and judge their abilities with beginners. They need to keep it simple and realise that we’re not all millionaires but that marine livestock need correct technical support. Information could be given by the dealer but hardware purchases made from somewhere else, the internet for example. It’s always worth a try – tell them the price an item can be obtained for and from where. They might just drop the price to obtain a sale.

Even if for example not all hardware is obtained from the dealers they’ll be happy if some livestock and ongoing requirements are because they are selling as they need to. The new aquarist will be happy because the dealer will get to know them and their aquarium.

Who knows, maybe a friendship will grow. ‘See you next week for coffee!’